SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and equipment, net (Details)	Dec. 31, 2025
Buildings
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	20 years
Electronic equipment \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	3 years
Electronic equipment \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	10 years
Furniture and fixture
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years
Transportation vehicles
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	4 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]	us-gaap:UsefulLifeShorterOfTermOfLeaseOrAssetUtilityMember

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Indicates description of term of useful life for property, plant, and equipment when not stated as numeric value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482190/360-10-35-3

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